Contribution of Extracellular Membrane Vesicles To the Secretome of Staphylococcus aureus
Divakara S. S. M. Uppu, Xiaogang Wang, Jean C. Lee
Abstract
The secretome of Staphylococcus aureus includes soluble molecules and nano-sized extracellular membrane vesicles (MVs). The protein composition of both the secretome and MVs includes cytoplasmic and membrane proteins, as well as exoproteins, some cell wall-associated proteins, and glycopolymers. How the MV cargo differs from the protein composition of the secretome has not yet been addressed. Although the compositions of the secretome and MVs were strikingly similar, we identified 54 proteins that were specifically packaged in MVs. Proteins highly associated with MVs were characterized by their abundance in the secretome, an association with the bacterial membrane, and a basic isoelectric point. This study deepens our limited understanding about the contribution of MVs to the secretome of S. aureus.